Lifting-jack



F. L. GORMLEY.

LIFTING JACK.

APPLICATION FILED MAR. 24' I919.-

Patented Mar. 23, 1920.

2 SHEETS-SHEET I.

Inventor: FrankL.Gorm1,e

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LIFTING JACK. APPLICATION FILED MAR. 24, m9. 'Jlfi3%%88@ Patented Mar.23, 1920.

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Irwenlor: Frank L. Gormley,

UNITED STATES PATENT OFFICE.

FRANK L. GORMLEY, OF CBEOOKLINE, MASSACHUSETTS, ASSIGNQR TO A. 0.NORTON, INC., 01 BOSTON, MASSACHUSETTS, A. CORPORATION OF MAINE.

LIFTING-JACK.

Specification of Letters Patent.

Patented Mar. 23, 1920.

Application filed March 24, 1919. Serial No. 284,842.

To all whom it may concern:

Be it known that I, FRANK L. GoRMnnr, a citizen of the United States ofAmerica, and a resident of Brookline, in the county of Norfolk andCommonwealth-of Massachusetts, have invented certain new and usefulImprovements in Lifting-Jacks, of which the following is aspecification.

This invention relates to lifting jacks and particularly to devices ofthis character de signed for heavy work, the object of the presentinvention being the provision of means whereby the lowering of themovable member under great loads may be either automatically or manuallycontrolled.

The invention is an improvement upon Letters Patent #1287366 granted tome Dec. 17, 1918.

The present invention consists in provid ing the jack with a revoluloleshaft having secured thereon a brake disk adapted to coact with amanually operated brake member, said shaft also being surrounded by anautomatic braking device operable under centrifugal action to impingeuponthe cylindrical wall ofa non-revoluble chamber within which saidautomatic governor operates.

The invention further consists of certain novel features of constructionand arrangement of parts which will be more fully understood byreference to the description of the drawings and t the claims tobehereinafter given.

F or the purpose of illustrating the invention, one preferred formthereof is illustrated in the drawings, this form having been found togive satisfactory and reliable results, although it is to be understoodthat the various instrumentalities of which the invention consists canbe variously arranged and organized and that the invention is notlimited to the precise arrangement and organization of theseinstrumentalities as herein shown and described, except as required bythe scope of the appended claims.

Of the drawings:

Figure 1 represents a horizontal section of a lifting jack embodying thefeatures of the present invention, the cutting plane being on line 1, 1on Fig. 2.

Fig. 2 represents a vertical section of the same on line 2, 2 on Fig. 1.

Fig. 3 represents a vertical section on line 3, 3 on Fig. 2, drawn to anenlarged scale.

like parts throughout the several figures of j the drawings.

In the drawings, represents a suitable base supporting a stationarystandard 11, over the outer periphery .of which is fitted amovablesleeve 12, to the upper end of which is threaded a cap 13.

In the upper end of the standard 11 is mounted a nut 14 to which isthreaded a lifting screw 15 having splined to itsupper reduced end abevel gear 16 with which meshes a bevel gear 17 formed upon or securedto a revoluble shaft or spindle 18, the outer end of which is providedwith a suitable operating mechanism 19 of any wellknown construction.

Between the upper face of the bevel gear 16 and the inner face of thecap 13 are two annular plates 20, 21, between which are interposed aplurality of anti-friction members 22.

The movable member 12 is provided on one sidewith a flanged projection24 having a removable plate 25 secured thereto by bolts 26.

The plate 25 is provided with a bearing 27 for the spindle 18, and keyedto said spindle 18 between the inner end of said bearing 27 and .therear face of the bevel gear 17, is a worm gear 28 rotatable in eitherdirection With the bevel gear 17.

The worm gear 28 meshes with a worm 29 formed upon or secured to a shaft30 revolubly mounted in cars 31, 32 projecting inwardly from the plate25.

On one end of the shaft 30 and adjacent to the car 32, are two collars33, 3 1 between which are interposed a plurality of antifriction members35, said collars 33, 34: being retained together by a ring 36 secured tothe collar 33 and having an annular flange 37 extending over the outerface of the collar 34:. The collars 33, 3a with the anti-frictionmembers form a thrust bearing for the shaft 30 on which the said thrustbearing is retained by a nut 38 threaded to the reduced end 39 of saidshaft.

Loosely mounted 011 the opposite end of the shaft 30 is a spur gear 4:0having a tapered annular flange 41 with which coaicts V a disk 42 keyedto the'shaft 80 and having a coneashapedperiphery adapted to contactwith the tapered flange 41 of the gear 40.

The disk 42 is retained upon the reduced end 43 of the shaft 30 by meansof the nut 44 threaded to said reduced end. When the movable member 12is being raised, the worm gear will be rotated in the direction .of thearrow at on'Figj 8 of the drawings and the disk 42 will be separatedfrom the flange 41 and no rotation will beimparted to the spur gear 40.

.lVhema load is on the cap 13 tending to lower the member 12, thetendency would be to rotate the worm gear 28 in a direction oppositetothat indicated by the arrow at and the worm shaft 30 would be movedendwiSe, toward the right of Fig. 3, until the cone-shaped,periphery ofthe disk 42 has been brought into firm contact with the ta peredflange41 on the gear40.

It; isv obvious that under these conditions any iro tary'movementimparted to the shaft keyed a brake disk 49.

The brake disk 49 is provided on one face with ears 50 to which arepivoted the links 51,-said linksfhaving pivoted to their opposite endsat 52, other .links 58, the opposite ends of which are pivoted to acollar 54 slidable uponthe rcduced'end 55 of the shaft 46.

" 1 This reduced end 55 of the shaft 46 is mounted in a bearing 56formed in a lug 57 formed uponthe'cover plate 25.

The collar 54 is preferably keyed to the reduced end 55 of shaft 46 asindicated in the drawings. V V V The cover plate 25 is also providedwith an inward projection 58"l1avi'ng a cylindrilcal chamber 5.9therein: g

;To each pivot member 52 is pivoted a friction pad 60 adapted to coactwith the wall of the chamber 59 when the shaft 46 rotates at apredetermined speed thereby preventing the load from being lowered toorapidly.

V 7 light helicalv spring 61 between the brake disk 49 and collar 54normally retains the collar in contact with the lug 57 with the frictionpads 60 free from contactwith the wall of the chamber 59. e

Any excessivespeed ofthe shaft 46 will tend'by-centrifugal action tomove the friction pads 60 outwardly intocontact with the wall of saidchamber 59 and by the frictional contact'of these pads 60 with saidwall, the H g speed of the shaft 46 will be retarded in an obviousmanner.

The cover plate 25 is provided with outwardly extending ears 62 to whichis pivoted a brake member 63, one arm of which is curved to contact withthe periphery of the brake disk 49 while the other arm 64 serves as ameans for manually separating said brake member 63 from the disk 49 whenit is desired to lower the load.

The brakemember 63 is normally held in contact with the periphery of thedisk 49 by means of the spring 65 positioned in a socket 66 formed inthe outwardly extending boss 67 of the cover plate 25.

The spring 65 acts upon a shoulder 68 formed on the outer end of thebrake member 63 as indicated in Fig. of the drawings.

As long as the brake member 63 is in contact with the disk 49, the worm29 will be prevented from rotating and as a consequence, there can be nodownward movement of the member 12.

The rapidity of the lowering of the member 12 will be automaticallycontrolled by the governor friction pads 60.

The pitch of the threads of the worm 29 is such that said worm may berotated by the rotation of the worm gear 28.

In the operation of the jack, the worm gear 28 is revolved in thedirection of the arrow a when raising the load and at the initialmovement of said gear 28, it will through the slight end movementimparted to the worm 29, disengage the members 41, 42 so that there willbe no brake devices or friction to retard the rotation of said gear.

lVhen, under the load, the gear 28 begins to rotate in the oppositedirection, the worm 29 will be moved in the opposite direction, the worm29 will be moved ondwise until the members 41, 42 are engaged and thenrotary movement will be imparted from the shaft to the short shaft 46through the gears 40, 45. At this time the brake member 63 will bedisengaged from the brake disk 49, said disengagement having beeneffected by the pressure of the hand of the operator upon the arm 64. a

When, on account of an excessive load upon the cap 13, the member 12moves downwardlytoo rapidly, the greater speed of the shaft 46 willcause the friction pads 60 to impinge upon the wall of the chamber 59and thereby automatically arrest the too rapid downward movement of themember 12.

When it is desired to arrest all further downward movement of the member12, pressure is removed from the arm 64 and the spring 65 will force thebrake member 63 into frictional contact with the periphery of the disk49 and further rotation of shaft 46 will be prevented.

This makes a very simple mechanism for controlling the lowering of thejack and it is believed that its operation and the many advantages ofthe invention will be readily understood without further description.

Having thus described my invention I claim: a

1. In a lifting jack, the combination of a revoluble operating shaft; aworm gear keyed to said operating shaft; a worm meshing with and adaptedto be rotated by said worm gear and having end movement; a gear looselymounted on the worm shaft; a member secured to said shaft adapted to bemoved with said shaft into driving engagement with said gear during thelowering operation; a revoluble shaft parallel to said worm shaft; apinion thereon meshing with said gear; a fixed cylindrical wallsurrounding said parallel shaft; toggle arms revoluble with saidparallel shaft; and friction pads secured to said toggle arms andadapted by centrifugal action to be forced into engagement with saidcylindrical Wall.

2. In a lifting jack, the combination of revoluble operating shaft aworm gear keyed to said operating shaft; a worm meshing with and adaptedto be rotated by said worm gear and having end movement; a gear looselymounted on the WOl'HlaShaft; a member secured to said shaft adapted tobe moved with said shaft into driving engagement with said gear duringthe lowering operation; a revoluble shaft parallel to said worm shaft; apinion thereon meshing With said gear; a fixed cylindrical Wallsurrounding said parallel shaft; toggle arms revoluble with saidparallel shaft; a collar slidable on said shaft to which one end of saidtoggle arms are pivoted; and friction pads secured to said toggle armsand adapted by centrifugal action to be forced into engagement with saidcylindrical wall.

3. In a lifting j ack, the combination of a revoluble operating shaft; aworm gear keyed to said operating shaft; a worm meshing with and adaptedto be rotated by said worm gear and having end movement; a gear looselymounted on the worm shaft; a member secured to said shaft adapted to bemoved with said shaft into driving engagement with said gear during thelowering operation; a revoluble shaft parallel to said worm shaft; apinion thereon meshing with said gear; a fixed cylindrical wallsurrounding said parallel shaft; toggle arms revoluble with saidparallel shaft; a collar slidable on said shaft to which one end of saidtoggle arms are pivoted; a light spring surrounding said parallel shaftand tending to straigthen said toggle arms; and friction pads secured tosaid toggle arms and adapted b centrifugal action to be forced intoengagement with said cylindrical wall.

Signed 'by me at 4: Post Oflice Square, Boston, Mass, this 21st day ofMarch, 1919.

FRANKL. GORMLEY. lVitnesses:

WALTER E. LOMBARD, NATHAN G. LOMBARD.

